1. Field of Invention
The present invention relates to vehicle rearview mirror and more particularly, to an auxiliary rearview mirror mounting structure that fits any of a variety of main rearview mirrors, facilitates mounting and dismounting the auxiliary rearview mirror, and enhances the mounting stability.
2. Description of Related Arts
FIG. 1 illustrates a conventional auxiliary rearview mirror mounting structure mounted at an outer lateral side of a main rearview mirror 30 of a car 20 to provide a wide angle rear view. Adding an auxiliary rearview mirror to each rearview mirror of a trailer would be of a great help. This design of auxiliary rearview mirror mounting structure, as shown in FIG. 2, comprises a pivot holder 50 mounted at a rear side of an auxiliary rearview mirror 10, a pair of support arms 40 pivotally connected to the pivot holder 50, and two binding straps 60 respectively extended from one support arm 40 and fastenable to the other support arm 40 to secure the two support arms 40 to a main rearview mirror 30. This design of auxiliary rearview mirror mounting structure can be seen in Taiwan Patent No.I256358.
FIG. 3 illustrates another prior art design of auxiliary rearview mirror mounting structure for fastening an auxiliary rearview mirror 10a to a main rearview mirror 30. This design of auxiliary rearview mirror mounting structure comprises a rod member 10b having an outer end pivotally connected to the auxiliary rearview mirror 10a, a plurality of hooking blocks 70 respectively slidably attached to the rod member 10b and locked thereto at respective selected locations with a respective lock screw 701, a strap 60 extended from one side of each hooking block 70 comprises and terminating in a hook 702, and a tightening-up device 703 mounted at each hooking block 70. Each tightening-up device 703 comprises a hand screw 7031 threaded through one respective hooking block 70 and terminating in a ball socket 7032, a rigid pad 7033 pivotally coupled to the ball socket 7032, and a flexible pad 7034 bonded to the rigid pad 7033. In installation, hook the hooks 702 on the rim 301 of the main rearview mirror 30, and then rotate the tightening-up devices 703 to rightly abut the flexible pads 7034 of the tightening-up devices 703 against the main rearview mirror 30.
However, because the straps 60 are made from flexible rubber, elastic fatigue can occur in the straps 60 after a long use. When the straps 60 get loose, they will not be closely attached to the back surface of the main rearview mirror 30, resulting in mounting instability. Further, if the straps 60 have different tensions, the auxiliary rearview mirror 10a and the main rearview mirror 30 will be vibrated during running of the vehicle, leading to image blur and the risk of falling of the auxiliary rearview mirror 10a from the main rearview mirror 30. Further, different main rearview mirrors 30 have a different shape and curvature of rim 301. The rod member 10b is not adjustable to fit the curvatures of the rims 301 of all different main rearview mirrors 30. Thus, the hooks 702 of the hooking device 70 cannot be positively hooked on the rims 301 of all different main rearview mirrors 30. Therefore, the conventional auxiliary rearview mirror mounting structure designs still have strong demand for improvement.